1) Field of the Invention
The present invention relates to N-substituted-3-[(2,3-dimethylmaleimido)amino]benzenesulfonamide derivatives, a preparation process thereof, and herbicidal compositions containing the derivatives as active ingredients.
2) Description of the Related Art
Numerous compounds have heretofore been proposed as herbicides. Regarding N-substituted benzenesulfonamide derivatives, a variety of compounds has also been reported as herbicides.
For example, EP-A-116518 and Japanese Patent Application Laid-Open (KOKAI) No. 129276/1987 disclose the use of N-(phenylsulfonyl)-N'-pyrimidyl- or triazinyl urea derivatives, which have one or more substituents on the phenyl nucleus, as herbicides. Illustrative of the substituent on the 3-position of the phenyl nucleus include various groups such as NHCH.sub.3, OCH.sub.2 CF.sub.3 and SCH.sub.2 CF.sub.3.
There have conventionally been strong demands for herbicides capable of exhibiting reliable herbicidal activity even at such low application dosages as bringing about the advantage of reducing the amount present in the environment, herbicides capable of exhibiting selectivity between crops and weeds irrespective of variations in environmental conditions, herbicides free from crop injury to the second crop in double cropping, etc. The present invention has been completed with a view toward meeting such demands.
The present inventors have found, as a result of an investigation, that a series of compounds still unreported in any publications known to the inventors and having a chemical structure different from the compounds disclosed in EP-A-116518 and Japanese Patent Application Laid-Open (KOKAI) No. 129276/1987 referred to above.